Evolution of Hand Held Phone

On April 3, 1973, Martin Cooper, a Motorola researcher and executive, made the first analogue mobile phone call using a heavy prototype model.
He called Dr. Joel S. Engel of Bell Labs.There was a long race between Motorola and Bell Labs to produce the first portable mobile phone.
Cooper is the first inventor named on "Radio telephone system" filed on October 17, 1973 with the US Patent Office and later issued as US Patent 3,906,166.
John F. Mitchell, Motorola's chief of portable communication products (and Cooper's boss) was also named on the patent.
He successfully pushed Motorola to develop wireless communication products that would be small enough to use anywhere and participated in the design of the cellular phone